924Board.org

[Stoney13]

After looking at all the carb options and speaking with several tuners. Most are telling me the CIS is superior to the carb choices in all ways. My hot start issue was explained to me its like airline lock in a diesel. Please correct me if i was misinformed.

So Ill be on holidays next week and have plenty of spare time. Ill be setting up a youtube account and going through this "rats nest" I would like to remove all the emissions control equipment that is unnecessary and it has a hot start button ghetto wired in.

Id appreciate all the help I can get and Ideola should be getting a bunch of my business right away first off with a CIS tester and tuneup kit, unless I can get a tester locally.
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I am car biased. Not brand wise or motor size. I don't like crap plain and simple.

1978 924 N/A

2011 Ford Ranger

[steve924]

The hot start problem in my experience is all about fuel pressure, or lack of it when the engine is switched off, causing vapour lock. The main offenders are Warm Up regulator, injectors and fuel accumulator. All of mine have been the warm up regulator on the manifold, most second hand ones seem to be sh%t so i put a new one on one of mine along with injectors, now its like new hot or cold, the injectors did wonders for performance and economy.

I checked the wur by switching off the engine once it was hot, clamping the fuel return line from the wur, waiting half hour or so releasing the clamp and the car started normally, crude but showed where the fault was.
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Porsche 924 na
porsche 924 1.8t

[Rocco R16V]

CIS is superior to carbs in every respect and when working good is a great system.
the main problem that renders CIS a major pain is when the car sits for years and the fuel goes bad and clogs up the entire system. since your car is running and has "minor" problems it should be fairly easy to fix with the right tools and knowledge, both available here.

One more thing that can cause hot start problems is a faulty check valve at the fuel pump that lets the system depresurize and allowing the fuel to vaporize easier.

good luck!

[Ozzie]

+1 to all above.

Starting at the rear the fault can be either one or many of the following
fuel pump non return valve
accumulator
CIS pressure regulator
injectors
WUR
Cold start valve

For me I replaced the CIS pressure regulator seal (cheap) and the injectors. I checked the remainder.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

[Khal]

[ic932]

You're an embarrassment to your country, you (i)gnorant (c)***.

Failure of the checkvalve is posssible but quite rare.
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BANNED

[Stoney13]

I am an ignorant wha ?

No your absolutely right. I am ignorant. And in fact, if you were too add up all that is knowable in the universe I would say I know pretty much *uck all.

At least I am smart enough to realize there are others who know more than I do.
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I am car biased. Not brand wise or motor size. I don't like crap plain and simple.

1978 924 N/A

2011 Ford Ranger

[Khal]

Trashing threads is what the troll does. Ignore it.
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'80 924 Turbo

[fiat22turbo]

Good grief, can Dave please get bounced? He's either trolling around, screwing up people's threads with his drunk posting (stop bloody drinking and posting!) or he's trying to sell crap to people all the time, not realizing that no one is going to buy anything from him due to his trolling.

As to the original post, there are a few books available on the Bosch CIS solution that can help guide you through fixing the minor issues you have.

Personally, I think it is an archaic system and it should be scrapped if it doesn't work as it would cost more to fix it than it would to setup an EFI solution.

With that said, however, if it already works and just needs some repairs, then it is a capable system and will scale to quite a bit more power than stock. Plus, there is a very knowledgeable group here that can usually diagnose most problems quite quickly.
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Stefan
1979 924 Carrera GTS (clone-ish)
1988 944 Turbo S (Silver Rose)

[Stoney13]

"And it's very important to follow the sequence of depressing the pedal to the floor and holding it there (until it starts) before activating the starter (else you'll have to wait several minutes before trying again)."

A little confused.

press gas pedal untill what starts ? befor activating the starter ?
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I am car biased. Not brand wise or motor size. I don't like crap plain and simple.

1978 924 N/A

2011 Ford Ranger

[Smoothie]

1) Depress and hold throttle pedal to the floor until further notice.
2) Insert and turn the key to make the starter (and engine) spin. Keep the starter activated until the engine starts (or until sufficient time's past that it's become obvious that it's not ever going to start). -Should generally start within 5-10 seconds though.
3) Once it kicks-in (engine starts running), release the throttle.
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"..it's made in Germany. You know the Germans always make good stuff."


'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

[Rasta Monsta]

Stefan overstates the problem, IMO. If CIS "doesn't work," a large percentage of the time the fault is in the WUR, and a rebuilt WUR will solve it. Once that is checked out, it seems that our accumulators are getting long in the tooth and in need of replacement.

$500 total for both jobs, plus an injector cleaning and new vacuum lines. 30 more years of good mileage, and clean reliable running.
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Toofah King Bad

• WeiBe (1987 924S 2.5t) - 931 S3

[Stoney13]

Takes 10 seconds of cranking to get my car to start via this method. Makes me think of the Ford 6.0 diesels that always are a pain to start.

Ran 3 bottles of fuel injector cleaner on an almost empty tank, added some fresh gas and a smidgen smother. Ill be starting a new thread when I get a couple of youtube videos up, for all those interested in pointing out what should be replaced adjusted or removed.
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I am car biased. Not brand wise or motor size. I don't like crap plain and simple.

1978 924 N/A

2011 Ford Ranger

[stevekat]

My primary start problem was the fuel pressure regulator integral to the fuel distributor. I picked up a new unit from EBS and screwed it in. Voila! My tiny o-ring had a chunk out of it or there was some debris in there, I cannot recall.
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"Never get out of the boat. Absolutely goddamn right. Unless you are goin' all the way."

Gone to new home: '81 924T, US version, CGT Intercooler, UTCIS-PT, Euro DITC, Greddy Trust MBC, Forged Fuchs Flat Dish 6's, Factory Recaro's.

[Stoney13]

So you replaced your whole fuel distributor ?
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I am car biased. Not brand wise or motor size. I don't like crap plain and simple.

1978 924 N/A

2011 Ford Ranger